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What is in the contrails that jets leave in the sky?

You may wish to review the Aircraft Contrails Factsheet.  This factsheet can be found at the URL: http://www.epa.gov/otaq/regs/nonroad/aviation/430f00005.pdf 

Also, a 1999 report issued by the Intergovernmental Panel on Climate Change entitled, "Aviation and the Global Atmosphere," discusses contrail formation and its effects in detail.  A copy of this report (ISBN number 0 521 66300 8) may be found through Cambridge University Press (cambridge.org) or a summary may be found on the IPCC website: http://www.ipcc.ch/pdf/special-reports/spm/av-en.pdf .  The influence of contrails on cirrus clouds is noted as a key area of scientific uncertainty that limits the ability to project aviation impacts on climate and ozone.

In regard to air quality impacts, jet aircraft contribute much less air pollution than that from motor vehicles, however, their overall emissions are increasing every year as air travel becomes more popular.  In addition, jet aircraft can contribute significantly to ground-level ambient air pollution in the immediate vicinity of an airport, especially emissions of nitrogen oxides (NOx) and hydrocarbons (HCs) which contribute to the formation of ozone.  Additional detailed information on aircraft emissions can be found in an EPA report, "Evaluation of Air Pollutant Emissions from Subsonic Commercial Jet Aircraft" (April 1999).  This report is also available at EPA’s aviation web site at: http://www.epa.gov/otaq/regs/nonroad/aviation/r99013.pdf

Information from the Air Force about military aircraft and their atmospheric and environmental effects can be found at www.af.mil/shared/media/document/AFD-051013-001.pdf.

Additional information from the EPA Office of Transportation and Air Quality (OTAQ) can be located at the following Web site:

Nonroad Engines, Equipment, and Vehicles: Aircraft,   http://www.epa.gov/otaq/aviation.htm
"This page provides information about air pollutant emissions from commercial aviation. It includes regulations, guidance, and other information related to aircraft."

With further question, you may wish to contact OTAQ, which has the resources to help you further.  They can be reached by e-mail at otaq@epa.gov, or via their Web form:  http://www.epa.gov/otaq/oms-cmt.htm

External Links Disclaimer: Please be aware that links to non-EPA sites do not imply any official EPA endorsement. Furthermore, EPA does not accept any responsibility for the opinions, ideas, data or products presented at those locations, or guarantee the validity of the information provided. EPA does not guarantee the suitability of the information for any specific purpose.

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Topic Information
  • Topic #: 23002-22394
  • Date Created: 7/22/2004
  • Last Modified Since: 2/5/2014
  • Viewed: 903

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